Systems and methods for repairing system files

ABSTRACT

A computer-implemented method for repairing system files may include 1) identifying a request to repair a corrupted system file in an operating system, 2) receiving file metadata describing the corrupted system file and system metadata describing the operating system, 3) identifying an uncorrupted version of the corrupted system file by i) identifying a series of matching tests for matching the corrupted system file with the uncorrupted version, the series of matching tests including at least one file metadata item from the file metadata and at least one system metadata item from the system metadata, and ii) applying the series of matching tests in a predetermined order to a database of uncorrupted system files until a matching test matches the corrupted system file with the uncorrupted version of the system file. Various other methods, systems, and computer-readable media are also disclosed.

BACKGROUND

Consumers and businesses face a growing tide of malicious software thatthreatens the stability and performance of their computers and thesecurity of their data. Computer programmers with malicious motivationshave created and continue to create viruses, Trojan horses, worms andother programs in an attempt to compromise computer systems. Thesemalicious programs are often referred to as malware. In an attempt toevade detection and removal, some exploits may inject malware intomalicious programmers may even inject malware into system files.

Traditional anti-malware systems may attempt to repair system files byidentifying malware injected into the system files and removing themalware while leaving the remainder of the system files intact.Unfortunately, traditional anti-malware systems may not always correctlyrepair infected system files. For example, traditional anti-malwaresystems may leave illegitimate portions of infected system files intactand/or remove legitimate portions of infected system files. In somecases, traditional anti-malware systems may determine that infectedsystem files cannot be repaired. Furthermore, polymorphic malware mayincrease the difficulty of isolating and removing malware from infectedsystem files. Accordingly, the instant disclosure identifies andaddresses a need for additional and improved systems and methods forrepairing system files.

SUMMARY

As will be described in greater detail below, the instant disclosuregenerally relates to systems and methods for repairing system files byusing a series of matching tests to match the file metadata and systemmetadata of corrupted system files with correct versions of clean systemfiles (and, e.g., replacing and/or repairing the corrupted system fileswith the clean system files). In one example, a computer-implementedmethod for repairing system files may include 1) identifying a requestto repair a corrupted system file in an operating system, 2) receivingfile metadata describing the corrupted system file and system metadatadescribing the operating system, 3) identifying an uncorrupted versionof the corrupted system file by i) identifying a series of matchingtests for matching the corrupted system file with the uncorruptedversion, the series of matching tests including at least one filemetadata item from the file metadata and at least one system metadataitem from the system metadata, and ii) applying the series of matchingtests in a predetermined order to a database of uncorrupted system filesuntil a matching test matches the corrupted system file with theuncorrupted version of the system file.

In some examples, receiving the file metadata may include receiving thecorrupted system file and parsing a portable executable header of thecorrupted system file for the file metadata. In some embodiments, thecomputer-implemented method may also include repairing the corruptedsystem file with the uncorrupted version of the system file. In theseembodiments, repairing the corrupted system file with the uncorruptedversion of the system file may include 1) identifying at least onedifference between the corrupted system file and the uncorrupted systemfile and 2) replacing the difference in the corrupted system file with acorresponding portion of the uncorrupted system file.

In one example, the series of matching tests may include a matching testcomparing the corrupted system file and each prospective match withinthe database of uncorrupted system files by comparing at least 1) achecksum of the corrupted system file and a checksum of the prospectivematch, 2) an operating system version of the operating system and anoperating system version of the prospective match, and 3) a file name ofthe corrupted system file and a file name of the prospective match. Inone embodiment, the series of matching tests may include a matching testcomparing the corrupted system file and each prospective match withinthe database of uncorrupted system files by comparing at least 1) a filearchitecture of the corrupted system file and a file architecture of theprospective match and 2) a file name of the corrupted system file and afile name of the prospective match.

In some embodiments, the series of matching tests may include a matchingtest comparing the corrupted system file and each prospective matchwithin the database of uncorrupted system files by comparing at least 1)a product name of the corrupted system file and a product name of theprospective match, 2) a product version of the corrupted system file anda product version of the prospective match, 3) a file architecture ofthe corrupted system file and a file architecture of the prospectivematch, and 4) a file name of the corrupted system file and a file nameof the prospective match. In some examples, the series of matching testsmay include a matching test comparing the corrupted system file and eachprospective match within the database of uncorrupted system files bycomparing at least 1) a service pack of the operating system and aservice pack of the operating system version of the prospective match,2) a hotfix of the operating system and a hotfix of the operating systemversion of the prospective match, 3) an architecture of the operatingsystem and an architecture of the operating system version of theprospective match, and 4) a file name of the corrupted system file and afile name of the prospective match.

In one embodiment, a system for implementing the above-described methodmay include 1) an identification module programmed to identify a requestto repair a corrupted system file in an operating system, 2) a receivingmodule programmed to receive file metadata describing the corruptedsystem file and system metadata describing the operating system, and 3)a matching module programmed to identify an uncorrupted version of thecorrupted system file by i) identifying a series of matching tests formatching the corrupted system file with the uncorrupted version, theseries of matching tests including at least one file metadata item fromthe file metadata and at least one system metadata item from the systemmetadata and ii) applying the series of matching tests in apredetermined order to a database of uncorrupted system files until amatching test matches the corrupted system file with the uncorruptedversion of the system file. The system may also include at least oneprocessor configured to execute the identification module, the receivingmodule, and the matching module.

In some examples, the above-described method may be encoded ascomputer-readable instructions on a computer-readable-storage medium.For example, a computer-readable-storage medium may include one or morecomputer-executable instructions that, when executed by at least oneprocessor of a computing device, may cause the computing device to 1)identify a request to repair a corrupted system file in an operatingsystem, 2) receive file metadata describing the corrupted system fileand system metadata describing the operating system, 3) identify anuncorrupted version of the corrupted system file by i) identifying aseries of matching tests for matching the corrupted system file with theuncorrupted version, the series of matching tests including at least onefile metadata item from the file metadata and at least one systemmetadata item from the system metadata, and ii) applying the series ofmatching tests in a predetermined order to a database of uncorruptedsystem files until a matching test matches the corrupted system filewith the uncorrupted version of the system file.

As will be explained in greater detail below, by using series ofmatching tests to match the file metadata and system metadata ofcorrupted system files with correct versions of clean system files (and,e.g., replacing and/or repairing the corrupted system files with theclean system files), the systems and methods described herein may fullyand correctly repair system files, even where malware within infectedsystem files is not identified and/or isolated.

Features from any of the above-mentioned embodiments may be used incombination with one another in accordance with the general principlesdescribed herein. These and other embodiments, features, and advantageswill be more fully understood upon reading the following detaileddescription in conjunction with the accompanying drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate a number of exemplary embodimentsand are a part of the specification. Together with the followingdescription, these drawings demonstrate and explain various principlesof the instant disclosure.

FIG. 1 is a block diagram of an exemplary system for repairing systemfiles.

FIG. 2 is a block diagram of an exemplary system for repairing systemfiles.

FIG. 3 is a flow diagram of an exemplary method for repairing systemfiles.

FIG. 4 is a block diagram of an exemplary system for repairing systemfiles.

FIG. 5 is a block diagram of an exemplary computing system capable ofimplementing one or more of the embodiments described and/or illustratedherein.

FIG. 6 is a block diagram of an exemplary computing network capable ofimplementing one or more of the embodiments described and/or illustratedherein.

Throughout the drawings, identical reference characters and descriptionsindicate similar, but not necessarily identical, elements. While theexemplary embodiments described herein are susceptible to variousmodifications and alternative forms, specific embodiments have beenshown by way of example in the drawings and will be described in detailherein. However, the exemplary embodiments described herein are notintended to be limited to the particular forms disclosed. Rather, theinstant disclosure covers all modifications, equivalents, andalternatives falling within the scope of the appended claims.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following will provide, with reference to FIGS. 1, 2, and 4,detailed descriptions of exemplary systems for repairing system files.Detailed descriptions of corresponding computer-implemented methods willalso be provided in connection with FIG. 3. In addition, detaileddescriptions of an exemplary computing system and network architecturecapable of implementing one or more of the embodiments described hereinwill be provided in connection with FIGS. 5 and 6, respectively.

FIG. 1 is a block diagram of an exemplary system 100 for repairingsystem files. As illustrated in this figure, exemplary system 100 mayinclude one or more modules 102 for performing one or more tasks. Forexample, and as will be explained in greater detail below, exemplarysystem 100 may include an identification module 104 programmed toidentify a request to repair a corrupted system file in an operatingsystem. Exemplary system 100 may also include a receiving module 106programmed to receive file metadata describing the corrupted system fileand system metadata describing the operating system.

In addition, and as will be described in greater detail below, exemplarysystem 100 may include a matching module 108 programmed to identify anuncorrupted version of the corrupted system file by i) identifying aseries of matching tests for matching the corrupted system file with theuncorrupted version, the series of matching tests including at least onefile metadata item from the file metadata and at least one systemmetadata item from the system metadata and ii) applying the series ofmatching tests in a predetermined order to a database of uncorruptedsystem files until a matching test matches the corrupted system filewith the uncorrupted version of the system file. Although illustrated asseparate elements, one or more of modules 102 in FIG. 1 may representportions of a single module or application.

In certain embodiments, one or more of modules 102 in FIG. 1 mayrepresent one or more software applications or programs that, whenexecuted by a computing device, may cause the computing device toperform one or more tasks. For example, and as will be described ingreater detail below, one or more of modules 102 may represent softwaremodules stored and configured to run on one or more computing devices,such as the devices illustrated in FIG. 2 (e.g., computing device 202and/or computing system 206), computing system 510 in FIG. 5, and/orportions of exemplary network architecture 600 in FIG. 6. One or more ofmodules 102 in FIG. 1 may also represent all or portions of one or morespecial-purpose computers configured to perform one or more tasks.

Exemplary system 100 in FIG. 1 may be implemented in a variety of ways.For example, all or a portion of exemplary system 100 may representportions of exemplary system 200 in FIG. 2. As shown in FIG. 2, system200 may include a computing device 202 in communication with a computingsystem 206 via a network 204 (e.g., to repair a corrupt system file 222on computing system 206).

In one embodiment, one or more of modules 102 from FIG. 1 may, whenexecuted by at least one processor of computing device 202, facilitatecomputing device 202 in repairing system files. For example, and as willbe described in greater detail below, one or more of modules 102 maycause computing device 202 to 1) identify a request 210 to repaircorrupt system file 222 in an operating system 220 (e.g., on computingsystem 206), 2) receive file metadata 230 describing corrupt system file222 and system metadata 232 describing operating system 220, 3) identifyan uncorrupted version of corrupt system file 222 (e.g., a system file252) by i) identifying a series of matching tests 240 for matchingcorrupt system file 222 with system file 252, matching tests 240including at least one file metadata item from file metadata 230 and atleast one system metadata item from system metadata 230, and ii)applying matching tests 240 in a predetermined order to a database 250of uncorrupted system files until a matching test matches corrupt systemfile 222 with system file 252.

Computing device 202 generally represents any type or form of computingdevice capable of reading computer-executable instructions. Examples ofcomputing device 202 include, without limitation, laptops, tablets,desktops, servers, cellular phones, personal digital assistants (PDAs),multimedia players, embedded systems, combinations of one or more of thesame, exemplary computing system 510 in FIG. 5, or any other suitablecomputing device.

Database 250 may represent portions of a single database or computingdevice or a plurality of databases or computing devices. For example,database 250 may represent a portion of computing device 202 in FIG. 2,computing system 510 in FIG. 5, and/or portions of exemplary networkarchitecture 600 in FIG. 6. Alternatively, database 250 may representone or more physically separate devices capable of being accessed by acomputing device, such as computing device 202 in FIG. 2, computingsystem 510 in FIG. 5, and/or portions of exemplary network architecture600 in FIG. 6.

Computing system 206 generally represents any type or form of computingdevice capable of reading computer-executable instructions. Examples ofcomputing device 202 include, without limitation, laptops, tablets,desktops, servers, cellular phones, personal digital assistants (PDAs),multimedia players, embedded systems, combinations of one or more of thesame, exemplary computing system 510 in FIG. 5, or any other suitablecomputing device.

Network 204 generally represents any medium or architecture capable offacilitating communication or data transfer. Examples of network 204include, without limitation, an intranet, a wide area network (WAN), alocal area network (LAN), a personal area network (PAN), the Internet,power line communications (PLC), a cellular network (e.g., a GSMNetwork), exemplary network architecture 600 in FIG. 6, or the like.Network 204 may facilitate communication or data transfer using wirelessor wired connections. In one embodiment, network 204 may facilitatecommunication between computing device 202 and server 206.

FIG. 3 is a flow diagram of an exemplary computer-implemented method 300for repairing system files. The steps shown in FIG. 3 may be performedby any suitable computer-executable code and/or computing system. Insome embodiments, the steps shown in FIG. 3 may be performed by one ormore of the components of system 100 in FIG. 1, system 200 in FIG. 2,computing system 510 in FIG. 5, and/or portions of exemplary networkarchitecture 600 in FIG. 6.

As illustrated in FIG. 3, at step 302 one or more of the systemsdescribed herein may identify a request to repair a corrupted systemfile in an operating system. For example, at step 302 identificationmodule 104 may, as part of computing device 202 in FIG. 2, identifyrequest 210 to repair corrupt system file 222 in an operating system 220(e.g., on computing system 206).

As used herein, the phrase “operating system” may refer to anycollection of components that manages resources (such as CPU usageand/or I/O requests) associated with a computing device and/orfacilitates communication between the computing device's hardware andsoftware. Accordingly, the operating system may include any of a varietyof system software, including operating system kernels, device drivers,utility software, interface software (e.g., window mangers), and thelike. As used herein, the phrase “system file” may refer to any fileused by an operating system in the execution of the operating system.For example, the system file may include a device driver. In someexamples, the phrase “system file” may refer to a file that is a part ofand/or interfaces directly with an operating system kernel to contributeto the operation of the operating system. Additionally or alternatively,the phrase “system file” may refer to a file that includescomputer-executable instructions and/or that may include an exploit togenerate computer-executable instructions, the contents of which maydepend on the attributes of an operating system (e.g., the version ofthe operating system) in order to ensure that the operating systemfunctions properly.

The corrupted system file may be corrupted in any of a variety of ways.For example, the corrupted system file may have been infected, damaged,and/or otherwise modified by malware. In some examples, the corruptedsystem file may have been modified by a system error, a user error,and/or a hardware failure. In some examples, the corrupted system filemay not operate correctly. Additionally or alternatively, the corruptedsystem file may operate but also perform illegitimate operations (e.g.,malware-directed operations). In some examples, the corrupted systemfile may operate correctly but may not meet a security standard (e.g.,because the corrupted system file was modified and is no longer atrusted file). Accordingly, the request to repair the corrupted systemfile may arise in any of a variety of contexts. For example, the requestto repair the corrupted file may arise from an anti-malware system thatdetected malware within the corrupted system file and/or a behavioralanomaly traced to the corrupted system file. Additionally oralternatively, the request to repair the corrupted system file may arisefrom an authentication system determining that the corrupted system filedoes not match any whitelisted system file (e.g., based on a fingerprintof the corrupted system file). In some examples, the request to repairthe corrupted system file may include a user-submitted request.

Identification module 104 may identify the request in any suitablemanner. For example, identification module 104 may receive a messagefrom a client system including the request. As will be explained ingreater detail below, in some examples, one or more of the systemsdescribed herein may receive the corrupted system file and/or metadataabout the corrupted system file. In these examples, identificationmodule 104 may identify the request simply by receiving the corruptedsystem file and/or the metadata.

FIG. 4 illustrates an exemplary system 400 for repairing corruptedsystem files. As shown in FIG. 4, exemplary system 400 may include aclient system 410, a request server 420, a clean file informationdatabase 430, and a clean file repository 440. Using FIG. 4 as anexample, at step 302 identification module 104 may, as a part of requestserver 420, identify a request (e.g., received from client system 410)to repair a corrupt system file 414 within an operating system 412 ofclient system 410.

Returning to FIG. 3, at step 304 one or more of the systems describedherein may receive file metadata describing the corrupted system fileand system metadata describing the operating system. For example, atstep 304 receiving module 106 may, as part of computing device 202 inFIG. 2, receive file metadata 230 describing corrupt system file 222 andsystem metadata 232 describing operating system 220.

As used herein, the phrase “file metadata” may refer to any attributeand/or characteristic of a file. In some examples, the file metadata mayinclude metadata stored within the corrupted system file (e.g., in adesignated metadata field). Additionally or alternatively, the filemetadata may include metadata managed by a system outside of thecorrupted system file (e.g., file system metadata managed by a filesystem in which the corrupted system file is stored). In some examples,the file metadata may include characteristics that may be derived and/orextracted from the corrupted system file upon analysis of the corruptedsystem file. Examples of file metadata include, without limitation, afile name, a file path, a file architecture, a checksum, a product name,a product version, a vendor name, a language, and the like.

As used herein, the phrase “system metadata” may refer to any attributeand/or characteristic of an operating system. Examples of systemmetadata include, without limitation, an operating system version, aservice pack identifier, a hotfix identifier, an operating systemarchitecture, an operating system language, and the like.

As mentioned earlier, receiving module 106 may receive the file metadatain any of a variety of ways. For example, receiving module 106 mayreceive a collection of metadata fields describing the corrupted systemfile. Additionally or alternatively, receiving module 106 may receivethe system file and extract metadata fields from the corrupted systemfile. In some examples, receiving module 106 may receive the system fileand analyze the system file to derive file metadata. In some examples,upon receiving the corrupted system file, receiving module 106 may parsea portable executable header of the corrupted system file for themetadata. As used herein, the phrase “portable executable header” mayrefer to any section of an executable file, object file, and/or libraryfile including metadata about the file. For example, the phrase“portable executable header” may refer to a header of a PortableExecutable file.

Using FIG. 4 as an example, at step 304 receiving module 106 may receivecorrupt system file 414 and system metadata describing operating system412 from client system 410. Receiving module 106 may also extract filemetadata from corrupt system file 414.

Returning to FIG. 3, at step 306 one or more of the systems describedherein may identify an uncorrupted version of the corrupted system fileby, in part, identifying a series of matching tests for matching thecorrupted system file with the uncorrupted version, the series ofmatching tests including at least one file metadata item from the filemetadata and at least one system metadata item from the system metadata.For example, at step 306 matching module 108 may, as part of computingdevice 202 in FIG. 2, identify an uncorrupted version of corrupt systemfile 222 (e.g., system file 252) by, in part, identifying matching tests240 for matching corrupt system file 222 with system file 252, matchingtests 240 including at least one file metadata item from file metadata230 and at least one system metadata item from system metadata 230.

The series of matching tests may include any tests for comparing thefile metadata and/or system metadata corresponding to the corruptedsystem file and the operating system of the corrupted system file withone or more clean system files (and, e.g., the operating systems towhich the clean system files correspond). The series of matching testsmay include tests of any format and/or procedure. For example, theseries of matching tests may include database queries for clean systemfiles that match each file metadata item and system metadata itemcorresponding to the corrupted system file that are specified by thematching test. For example, each matching test may include a combinationof file metadata items and system metadata items to match.

The matching tests may include any of a variety of combinations ofmetadata fields to match. For example, the series of matching tests mayinclude a matching test comparing the corrupted system file and eachprospective match within the database of uncorrupted system files bycomparing at least 1) a checksum of the corrupted system file and achecksum of the prospective match, 2) an operating system version of theoperating system and an operating system version of the prospectivematch, and 3) a file name of the corrupted system file and a file nameof the prospective match. As used herein, the term “checksum” may referto any checksum, fingerprint, hash, and/or other unique representationof a string of data. For example, the checksum may include a MD5 hashvalue. Additionally or alternatively, the checksum may include a SHA-256hash value. The checksum may include any checksum generated before thecorrupted system file was corrupted. For example, the checksum mayinclude a checksum generated by a compiler and/or linker at the originaltime of compilation of the corrupted system file. The operating systemversion may include any information identifying the version of theoperating system. For example, the operating system version may includea major operating system version and/or minor operating system version.

In one embodiment, the series of matching tests may include a matchingtest comparing the corrupted system file and each prospective matchwithin the database of uncorrupted system files by comparing at least 1)a file architecture of the corrupted system file and a file architectureof the prospective match and 2) a file name of the corrupted system fileand a file name of the prospective match. In some examples, the matchingtest may also include language-based file version information and alanguage of the file (e.g., as identified in a header of the file).Additionally or alternatively, the matching test may includelanguage-independent file version information. The file architecture mayinclude any information relating to the instruction set architecture forwhich the corrupted system file is configured.

In some examples, the series of matching tests may include a matchingtest comparing the corrupted system file and each prospective matchwithin the database of uncorrupted system files by comparing at least 1)a product name of the corrupted system file and a product name of theprospective match, 2) a product version of the corrupted system file anda product version of the prospective match, 3) a file architecture ofthe corrupted system file and a file architecture of the prospectivematch, and 4) a file name of the corrupted system file and a file nameof the prospective match. The product name may include any name and/oridentifier by which the system file may be known (e.g., beyond a filesystem name). For example, the product name may include a name chosen bya vendor to represent the system file. Likewise, the product version mayinclude a version identifier designated by a vendor for the currentversion of the system file.

In some examples, the series of matching tests may include a matchingtest comparing the corrupted system file and each prospective matchwithin the database of uncorrupted system files by comparing at least 1)a service pack of the operating system and a service pack of theoperating system version of the prospective match, 2) a hotfix of theoperating system and a hotfix of the operating system version of theprospective match, 3) an architecture of the operating system and anarchitecture of the operating system version of the prospective match,and 4) a file name of the corrupted system file and a file name of theprospective match. The service pack metadata may include any informationabout any revision, update, fix, and/or enhancement to an operatingsystem. In some examples, matching module 108 may match incrementalservice packs with corresponding cumulative service packs. The hotfixmetadata may include any information about one or more patches appliedto an operating system (e.g. to fix specific bugs in the operatingsystem). The metadata identifying the architecture of the operatingsystem may identify any information relating to an instruction setarchitecture for which the operating system is configured.

Matching module 108 may identify the series of matching tests in anysuitable manner. For example, matching module 108 may identify theseries of matching tests by reading a configuration file specifying theseries of matching tests. Additionally or alternatively, matching module108 may include one or more hard-coded matching tests. Accordingly,matching module 108 may identify the hard-coded matching tests byloading the matching tests.

Returning to FIG. 3, at step 308 one or more of the systems describedherein may identify an uncorrupted version of the corrupted system fileby, in part, identify an uncorrupted version of the corrupted systemfile by, in part, applying the series of matching tests in apredetermined order to a database of uncorrupted system files until amatching test matches the corrupted system file with the uncorruptedversion of the system file. For example, at step 308 matching module 108may, as part of computing device 202 in FIG. 2, identify an uncorruptedversion of corrupt system file 222 (e.g., system file 252) by, in part,identify an uncorrupted version of corrupt system file 222 (e.g., asystem file 252) by, in part, applying matching tests 240 in apredetermined order to database 250 of uncorrupted system files until amatching test matches corrupt system file 222 with system file 252.

As mentioned above, matching module 108 may apply the series of matchingtests in a predetermined order until one of the matching tests resultsin a unique match. Accordingly, the matching tests may be arranged in anorder from most precise and/or strict to least precise and/or strict.For example, earlier matching tests in the series may include more filemetadata items while later matching tests in the series may include moresystem metadata items.

In one example, the matching module 108 may apply the following seriesof matching tests, in order: 1) testing for a match of the linkerchecksum of the corrupted system file, the file name of the corruptedsystem file, and the major and minor versions of the operating system,2) testing for a match of language-based file version information of thecorrupted system file, the language (e.g., localization) of thecorrupted system file, the architecture of the corrupted system file andthe file name of the corrupted system file, 3) testing for a match oflanguage-independent file version information of the corrupted systemfile, the architecture of the corrupted system file, and the file nameof the corrupted system file, 4) testing for a match oflanguage-independent file version information of the corrupted systemfile, a neutral language (e.g., localization), and the architecture ofthe corrupted system file, 5) testing for a match of language-basedproduct name information of the corrupted system file, language-basedproduct version information of the corrupted system file, thearchitecture of the corrupted system file, the file name of thecorrupted system file, the operating system service pack number of theoperating system, and any operating system hotfixes applied to theoperating system, and 6) testing for a match of the operating systemmajor and minor versions, the service pack number of the operatingsystem, any hotfixes applied to the operating system, an architecture ofthe operating system, a language of the operating system, and the nameof the file.

Using FIG. 4 as an example, at step 308 matching module 108 may, as apart of request server 420, submit a series of queries to clean fileinformation database 430 with metadata from corrupt system file 414 andoperating system 412 until a unique matching clean system file isidentified by clean file information database 430 (e.g., clean systemfile 442).

In some examples, one or more of the systems described herein may alsorepair the corrupted system file. For example, a repair module on thecomputing device of the operating system may repair the corrupted systemmodule. The repair module may repair the corrupted system file in anysuitable manner. For example, the repair module may repair the corruptedsystem file with the uncorrupted version of the system file identifiedby matching module 108. In some examples, the repair module may identifyat least one difference between the corrupted system file and theuncorrupted version of the system file and then replace the differencein the corrupted system file with a corresponding portion of theuncorrupted system file. Additionally or alternatively, matching module108 may simply replace the corrupted system file with the uncorruptedversion of the system file.

Using FIG. 4 as an example, request server 420 may retrieve clean systemfile 442 from clean file repository, having identified clean system file442 as the uncorrupted version of corrupt system file 414. Requestserver 420 may then generate a file diff 422 based on the differencebetween corrupt system file 414 and clean system file 442. Requestserver 420 may then respond to the request of client system 410 byproviding file diff 422 to client system 410. A repair module 418 onclient system 410 may then create a repaired system file 416 based oncorrupt system file 414 and file diff 422.

As explained above, by using series of matching tests to match the filemetadata and system metadata of corrupted system files with correctversions of clean system files (and, e.g., replacing and/or repairingthe corrupted system files with the clean system files), the systems andmethods described herein may fully and correctly repair system files,even where malware within infected system files is not identified and/orisolated.

FIG. 5 is a block diagram of an exemplary computing system 510 capableof implementing one or more of the embodiments described and/orillustrated herein. For example, all or a portion of computing system510 may perform and/or be a means for performing, either alone or incombination with other elements, one or more of the identifying,receiving, parsing, matching, applying, repairing, and replacing stepsdescribed herein. All or a portion of computing system 510 may alsoperform and/or be a means for performing any other steps, methods, orprocesses described and/or illustrated herein.

Computing system 510 broadly represents any single or multi-processorcomputing device or system capable of executing computer-readableinstructions. Examples of computing system 510 include, withoutlimitation, workstations, laptops, client-side terminals, servers,distributed computing systems, handheld devices, or any other computingsystem or device. In its most basic configuration, computing system 510may include at least one processor 514 and a system memory 516.

Processor 514 generally represents any type or form of processing unitcapable of processing data or interpreting and executing instructions.In certain embodiments, processor 514 may receive instructions from asoftware application or module. These instructions may cause processor514 to perform the functions of one or more of the exemplary embodimentsdescribed and/or illustrated herein.

System memory 516 generally represents any type or form of volatile ornon-volatile storage device or medium capable of storing data and/orother computer-readable instructions. Examples of system memory 516include, without limitation, random access memory (RAM), read onlymemory (ROM), flash memory, or any other suitable memory device.Although not required, in certain embodiments computing system 510 mayinclude both a volatile memory unit (such as, for example, system memory516) and a non-volatile storage device (such as, for example, primarystorage device 532, as described in detail below). In one example, oneor more of modules 102 from FIG. 1 may be loaded into system memory 516.

In certain embodiments, exemplary computing system 510 may also includeone or more components or elements in addition to processor 514 andsystem memory 516. For example, as illustrated in FIG. 5, computingsystem 510 may include a memory controller 518, an Input/Output (I/O)controller 520, and a communication interface 522, each of which may beinterconnected via a communication infrastructure 512. Communicationinfrastructure 512 generally represents any type or form ofinfrastructure capable of facilitating communication between one or morecomponents of a computing device. Examples of communicationinfrastructure 512 include, without limitation, a communication bus(such as an ISA, PCI, PCIe, or similar bus) and a network.

Memory controller 518 generally represents any type or form of devicecapable of handling memory or data or controlling communication betweenone or more components of computing system 510. For example, in certainembodiments memory controller 518 may control communication betweenprocessor 514, system memory 516, and I/O controller 520 viacommunication infrastructure 512.

I/O controller 520 generally represents any type or form of modulecapable of coordinating and/or controlling the input and outputfunctions of a computing device. For example, in certain embodiments I/Ocontroller 520 may control or facilitate transfer of data between one ormore elements of computing system 510, such as processor 514, systemmemory 516, communication interface 522, display adapter 526, inputinterface 530, and storage interface 534.

Communication interface 522 broadly represents any type or form ofcommunication device or adapter capable of facilitating communicationbetween exemplary computing system 510 and one or more additionaldevices. For example, in certain embodiments communication interface 522may facilitate communication between computing system 510 and a privateor public network including additional computing systems. Examples ofcommunication interface 522 include, without limitation, a wired networkinterface (such as a network interface card), a wireless networkinterface (such as a wireless network interface card), a modem, and anyother suitable interface. In at least one embodiment, communicationinterface 522 may provide a direct connection to a remote server via adirect link to a network, such as the Internet. Communication interface522 may also indirectly provide such a connection through, for example,a local area network (such as an Ethernet network), a personal areanetwork, a telephone or cable network, a cellular telephone connection,a satellite data connection, or any other suitable connection.

In certain embodiments, communication interface 522 may also represent ahost adapter configured to facilitate communication between computingsystem 510 and one or more additional network or storage devices via anexternal bus or communications channel. Examples of host adaptersinclude, without limitation, SCSI host adapters, USB host adapters, IEEE1394 host adapters, SATA and eSATA host adapters, ATA and PATA hostadapters, Fibre Channel interface adapters, Ethernet adapters, or thelike. Communication interface 522 may also allow computing system 510 toengage in distributed or remote computing. For example, communicationinterface 522 may receive instructions from a remote device or sendinstructions to a remote device for execution.

As illustrated in FIG. 5, computing system 510 may also include at leastone display device 524 coupled to communication infrastructure 512 via adisplay adapter 526. Display device 524 generally represents any type orform of device capable of visually displaying information forwarded bydisplay adapter 526. Similarly, display adapter 526 generally representsany type or form of device configured to forward graphics, text, andother data from communication infrastructure 512 (or from a framebuffer, as known in the art) for display on display device 524.

As illustrated in FIG. 5, exemplary computing system 510 may alsoinclude at least one input device 528 coupled to communicationinfrastructure 512 via an input interface 530. Input device 528generally represents any type or form of input device capable ofproviding input, either computer or human generated, to exemplarycomputing system 510. Examples of input device 528 include, withoutlimitation, a keyboard, a pointing device, a speech recognition device,or any other input device.

As illustrated in FIG. 5, exemplary computing system 510 may alsoinclude a primary storage device 532 and a backup storage device 533coupled to communication infrastructure 512 via a storage interface 534.Storage devices 532 and 533 generally represent any type or form ofstorage device or medium capable of storing data and/or othercomputer-readable instructions. For example, storage devices 532 and 533may be a magnetic disk drive (e.g., a so-called hard drive), a solidstate drive, a floppy disk drive, a magnetic tape drive, an optical diskdrive, a flash drive, or the like. Storage interface 534 generallyrepresents any type or form of interface or device for transferring databetween storage devices 532 and 533 and other components of computingsystem 510.

In certain embodiments, storage devices 532 and 533 may be configured toread from and/or write to a removable storage unit configured to storecomputer software, data, or other computer-readable information.Examples of suitable removable storage units include, withoutlimitation, a floppy disk, a magnetic tape, an optical disk, a flashmemory device, or the like. Storage devices 532 and 533 may also includeother similar structures or devices for allowing computer software,data, or other computer-readable instructions to be loaded intocomputing system 510. For example, storage devices 532 and 533 may beconfigured to read and write software, data, or other computer-readableinformation. Storage devices 532 and 533 may also be a part of computingsystem 510 or may be a separate device accessed through other interfacesystems.

Many other devices or subsystems may be connected to computing system510. Conversely, all of the components and devices illustrated in FIG. 5need not be present to practice the embodiments described and/orillustrated herein. The devices and subsystems referenced above may alsobe interconnected in different ways from that shown in FIG. 5. Computingsystem 510 may also employ any number of software, firmware, and/orhardware configurations. For example, one or more of the exemplaryembodiments disclosed herein may be encoded as a computer program (alsoreferred to as computer software, software applications,computer-readable instructions, or computer control logic) on acomputer-readable-storage medium. The phrase “computer-readable-storagemedium” generally refers to any form of device, carrier, or mediumcapable of storing or carrying computer-readable instructions. Examplesof computer-readable-storage media include, without limitation,transmission-type media, such as carrier waves, and non-transitory-typemedia, such as magnetic-storage media (e.g., hard disk drives and floppydisks), optical-storage media (e.g., CD- or DVD-ROMs),electronic-storage media (e.g., solid-state drives and flash media), andother distribution systems.

The computer-readable-storage medium containing the computer program maybe loaded into computing system 510. All or a portion of the computerprogram stored on the computer-readable-storage medium may then bestored in system memory 516 and/or various portions of storage devices532 and 533. When executed by processor 514, a computer program loadedinto computing system 510 may cause processor 514 to perform and/or be ameans for performing the functions of one or more of the exemplaryembodiments described and/or illustrated herein. Additionally oralternatively, one or more of the exemplary embodiments described and/orillustrated herein may be implemented in firmware and/or hardware. Forexample, computing system 510 may be configured as an applicationspecific integrated circuit (ASIC) adapted to implement one or more ofthe exemplary embodiments disclosed herein.

FIG. 6 is a block diagram of an exemplary network architecture 600 inwhich client systems 610, 620, and 630 and servers 640 and 645 may becoupled to a network 650. As detailed above, all or a portion of networkarchitecture 600 may perform and/or be a means for performing, eitheralone or in combination with other elements, one or more of theidentifying, receiving, parsing, matching, applying, repairing, andreplacing steps disclosed herein. All or a portion of networkarchitecture 600 may also be used to perform and/or be a means forperforming other steps and features set forth in the instant disclosure.

Client systems 610, 620, and 630 generally represent any type or form ofcomputing device or system, such as exemplary computing system 510 inFIG. 5. Similarly, servers 640 and 645 generally represent computingdevices or systems, such as application servers or database servers,configured to provide various database services and/or run certainsoftware applications. Network 650 generally represents anytelecommunication or computer network including, for example, anintranet, a wide area network (WAN), a local area network (LAN), apersonal area network (PAN), or the Internet. In one example, clientsystems 610, 620, and/or 630 and/or servers 640 and/or 645 may includeall or a portion of system 100 from FIG. 1.

As illustrated in FIG. 6, one or more storage devices 660(1)-(N) may bedirectly attached to server 640. Similarly, one or more storage devices670(1)-(N) may be directly attached to server 645. Storage devices660(1)-(N) and storage devices 670(1)-(N) generally represent any typeor form of storage device or medium capable of storing data and/or othercomputer-readable instructions. In certain embodiments, storage devices660(1)-(N) and storage devices 670(1)-(N) may represent network-attachedstorage (NAS) devices configured to communicate with servers 640 and 645using various protocols, such as NFS, SMB, or CIFS.

Servers 640 and 645 may also be connected to a storage area network(SAN) fabric 680. SAN fabric 680 generally represents any type or formof computer network or architecture capable of facilitatingcommunication between a plurality of storage devices. SAN fabric 680 mayfacilitate communication between servers 640 and 645 and a plurality ofstorage devices 690(1)-(N) and/or an intelligent storage array 695. SANfabric 680 may also facilitate, via network 650 and servers 640 and 645,communication between client systems 610, 620, and 630 and storagedevices 690(1)-(N) and/or intelligent storage array 695 in such a mannerthat devices 690(1)-(N) and array 695 appear as locally attached devicesto client systems 610, 620, and 630. As with storage devices 660(1)-(N)and storage devices 670(1)-(N), storage devices 690(1)-(N) andintelligent storage array 695 generally represent any type or form ofstorage device or medium capable of storing data and/or othercomputer-readable instructions.

In certain embodiments, and with reference to exemplary computing system510 of FIG. 5, a communication interface, such as communicationinterface 522 in FIG. 5, may be used to provide connectivity betweeneach client system 610, 620, and 630 and network 650. Client systems610, 620, and 630 may be able to access information on server 640 or 645using, for example, a web browser or other client software. Suchsoftware may allow client systems 610, 620, and 630 to access datahosted by server 640, server 645, storage devices 660(1)-(N), storagedevices 670(1)-(N), storage devices 690(1)-(N), or intelligent storagearray 695. Although FIG. 6 depicts the use of a network (such as theInternet) for exchanging data, the embodiments described and/orillustrated herein are not limited to the Internet or any particularnetwork-based environment.

In at least one embodiment, all or a portion of one or more of theexemplary embodiments disclosed herein may be encoded as a computerprogram and loaded onto and executed by server 640, server 645, storagedevices 660(1)-(N), storage devices 670(1)-(N), storage devices690(1)-(N), intelligent storage array 695, or any combination thereof.All or a portion of one or more of the exemplary embodiments disclosedherein may also be encoded as a computer program, stored in server 640,run by server 645, and distributed to client systems 610, 620, and 630over network 650.

As detailed above, computing system 510 and/or one or more components ofnetwork architecture 600 may perform and/or be a means for performing,either alone or in combination with other elements, one or more steps ofan exemplary method for repairing system files.

While the foregoing disclosure sets forth various embodiments usingspecific block diagrams, flowcharts, and examples, each block diagramcomponent, flowchart step, operation, and/or component described and/orillustrated herein may be implemented, individually and/or collectively,using a wide range of hardware, software, or firmware (or anycombination thereof) configurations. In addition, any disclosure ofcomponents contained within other components should be consideredexemplary in nature since many other architectures can be implemented toachieve the same functionality.

In some examples, all or a portion of exemplary system 100 in FIG. 1 mayrepresent portions of a cloud-computing or network-based environment.Cloud-computing environments may provide various services andapplications via the Internet. These cloud-based services (e.g.,software as a service, platform as a service, infrastructure as aservice, etc.) may be accessible through a web browser or other remoteinterface. Various functions described herein may be provided through aremote desktop environment or any other cloud-based computingenvironment.

The process parameters and sequence of steps described and/orillustrated herein are given by way of example only and can be varied asdesired. For example, while the steps illustrated and/or describedherein may be shown or discussed in a particular order, these steps donot necessarily need to be performed in the order illustrated ordiscussed. The various exemplary methods described and/or illustratedherein may also omit one or more of the steps described or illustratedherein or include additional steps in addition to those disclosed.

While various embodiments have been described and/or illustrated hereinin the context of fully functional computing systems, one or more ofthese exemplary embodiments may be distributed as a program product in avariety of forms, regardless of the particular type ofcomputer-readable-storage media used to actually carry out thedistribution. The embodiments disclosed herein may also be implementedusing software modules that perform certain tasks. These softwaremodules may include script, batch, or other executable files that may bestored on a computer-readable storage medium or in a computing system.In some embodiments, these software modules may configure a computingsystem to perform one or more of the exemplary embodiments disclosedherein.

In addition, one or more of the modules described herein may transformdata, physical devices, and/or representations of physical devices fromone form to another. For example, one or more of the modules recitedherein may transform a computing device into a device for repairingsystem files. As another example, one or more of the modules recitedherein may transform a computing device into a device for identifying aclean version of a corrupted system file. As another example, one ormore of the modules recited herein may transform a corrupted system fileinto a clean system file.

The preceding description has been provided to enable others skilled inthe art to best utilize various aspects of the exemplary embodimentsdisclosed herein. This exemplary description is not intended to beexhaustive or to be limited to any precise form disclosed. Manymodifications and variations are possible without departing from thespirit and scope of the instant disclosure. The embodiments disclosedherein should be considered in all respects illustrative and notrestrictive. Reference should be made to the appended claims and theirequivalents in determining the scope of the instant disclosure.

Unless otherwise noted, the terms “a” or “an,” as used in thespecification and claims, are to be construed as meaning “at least oneof.” In addition, for ease of use, the words “including” and “having,”as used in the specification and claims, are interchangeable with andhave the same meaning as the word “comprising.”

What is claimed is:
 1. A computer-implemented method for repairingsystem files, at least a portion of the method being performed by acomputing device comprising at least one processor, the methodcomprising: identifying a request to repair a corrupted system file inan operating system; receiving file metadata describing the corruptedsystem file and system metadata describing the operating system;identifying an uncorrupted version of the corrupted system file by:identifying a series of matching tests for matching the corrupted systemfile with the uncorrupted version, the series of matching testscomprising at least one file metadata item from the file metadata and atleast one system metadata item from the system metadata; applying theseries of matching tests in a predetermined order to a database ofuncorrupted system files until a matching test matches the corruptedsystem file with the uncorrupted version of the system file.
 2. Thecomputer-implemented method of claim 1, further comprising repairing thecorrupted system file with the uncorrupted version of the system file,wherein the corrupted system file comprises a system file used by theoperating system in execution of the operating system.
 3. Thecomputer-implemented method of claim 2, wherein repairing the corruptedsystem file with the uncorrupted version of the system file comprises:identifying at least one difference between the corrupted system fileand the uncorrupted system file; replacing the difference in thecorrupted system file with a corresponding portion of the uncorruptedsystem file.
 4. The computer-implemented method of claim 1, whereinreceiving the file metadata comprises: receiving the corrupted systemfile; parsing a portable executable header of the corrupted system filefor the file metadata.
 5. The computer-implemented method of claim 1,wherein the series of matching tests comprises a matching test comparingthe corrupted system file and each prospective match within the databaseof uncorrupted system files by comparing at least: a checksum of thecorrupted system file and a checksum of the prospective match; anoperating system version of the operating system and an operating systemversion of the prospective match; a file name of the corrupted systemfile and a file name of the prospective match.
 6. Thecomputer-implemented method of claim 1, wherein the series of matchingtests comprises a matching test comparing the corrupted system file andeach prospective match within the database of uncorrupted system filesby comparing at least: a file architecture of the corrupted system fileand a file architecture of the prospective match; a file name of thecorrupted system file and a file name of the prospective match.
 7. Thecomputer-implemented method of claim 1, wherein the series of matchingtests comprises a matching test comparing the corrupted system file andeach prospective match within the database of uncorrupted system filesby comparing at least: a product name of the corrupted system file and aproduct name of the prospective match; a product version of thecorrupted system file and a product version of the prospective match; afile architecture of the corrupted system file and a file architectureof the prospective match; a file name of the corrupted system file and afile name of the prospective match.
 8. The computer-implemented methodof claim 1, wherein: the corrupted system file comprises a file that isinfected with malware; the computer-implemented method further comprisesusing the series of matching tests to repair the corrupted system fileby identifying a difference between the corrupted system file and theuncorrupted version and replacing the difference in the corrupted systemfile with a corresponding portion of the uncorrupted version.
 9. Asystem for repairing system files, the system comprising: anidentification module programmed to identify a request to repair acorrupted system file in an operating system; a receiving moduleprogrammed to receive file metadata describing the corrupted system fileand system metadata describing the operating system; a matching moduleprogrammed to identify an uncorrupted version of the corrupted systemfile by: identifying a series of matching tests for matching thecorrupted system file with the uncorrupted version, the series ofmatching tests comprising at least one file metadata item from the filemetadata and at least one system metadata item from the system metadata;applying the series of matching tests in a predetermined order to adatabase of uncorrupted system files until a matching test matches thecorrupted system file with the uncorrupted version of the system file;at least one hardware processor configured to execute the identificationmodule, the receiving module, and the matching module.
 10. The system ofclaim 9, further comprising a repair module programmed to repair thecorrupted system file with the uncorrupted version of the system file,wherein the system file comprises a file that interfaces directly with akernel of the operating system to contribute to operation of theoperating system.
 11. The system of claim 10, wherein the repair moduleis programmed to repair the corrupted system file with the uncorruptedversion of the system file by: identifying at least one differencebetween the corrupted system file and the uncorrupted system file;replacing the difference in the corrupted system file with acorresponding portion of the uncorrupted system file.
 12. The system ofclaim 9, wherein the receiving module is programmed to receive the filemetadata by: receiving the corrupted system file; parsing a portableexecutable header of the corrupted system file for the file metadata.13. The system of claim 9, wherein the series of matching testscomprises a matching test comparing the corrupted system file and eachprospective match within the database of uncorrupted system files bycomparing at least: a checksum of the corrupted system file and achecksum of the prospective match; an operating system version of theoperating system and an operating system version of the prospectivematch; a file name of the corrupted system file and a file name of theprospective match.
 14. The system of claim 9, wherein the series ofmatching tests comprises a matching test comparing the corrupted systemfile and each prospective match within the database of uncorruptedsystem files by comparing at least: a file architecture of the corruptedsystem file and a file architecture of the prospective match; a filename of the corrupted system file and a file name of the prospectivematch.
 15. The system of claim 9, wherein the series of matching testscomprises a matching test comparing the corrupted system file and eachprospective match within the database of uncorrupted system files bycomparing at least: a product name of the corrupted system file and aproduct name of the prospective match; a product version of thecorrupted system file and a product version of the prospective match; afile architecture of the corrupted system file and a file architectureof the prospective match; a file name of the corrupted system file and afile name of the prospective match.
 16. The system of claim 9, whereinthe series of matching tests comprises a matching test comparing thecorrupted system file and each prospective match within the database ofuncorrupted system files by comparing at least: an operating systemversion of the operating system and an operating system version of theprospective match; a service pack of the operating system and a servicepack of the operating system version of the prospective match; a hotfixof the operating system and a hotfix of the operating system version ofthe prospective match; an architecture of the operating system and anarchitecture of the operating system version of the prospective match; afile name of the corrupted system file and a file name of theprospective match.
 17. A non-transitory computer-readable-storage mediumcomprising one or more computer-executable instructions that, whenexecuted by at least one processor of a computing device, cause thecomputing device to: identify a request to repair a corrupted systemfile in an operating system; receive file metadata describing thecorrupted system file and system metadata describing the operatingsystem; identify an uncorrupted version of the corrupted system file by:identifying a series of matching tests for matching the corrupted systemfile with the uncorrupted version, the series of matching testscomprising at least one file metadata item from the file metadata and atleast one system metadata item from the system metadata; applying theseries of matching tests in a predetermined order to a database ofuncorrupted system files until a matching test matches the corruptedsystem file with the uncorrupted version of the system file.
 18. Thecomputer-readable-storage medium of claim 17, wherein the one or morecomputer-executable instructions further cause the computing device torepair the corrupted system file with the uncorrupted version of thesystem file.
 19. The computer-readable-storage medium of claim 18,wherein the one or more computer-executable instructions cause thecomputing device to repair the corrupted system file with theuncorrupted version of the system file by causing the computing deviceto: identify at least one difference between the corrupted system fileand the uncorrupted system file; replace the difference in the corruptedsystem file with a corresponding portion of the uncorrupted system file.20. The computer-readable-storage medium of claim 17, wherein the one ormore computer-executable instructions cause the computing device toreceive the file metadata by causing the computing device to: receivethe corrupted system file; parse a portable executable header of thecorrupted system file for the file metadata.